810161591 has 4 divisors (see below), whose sum is σ = 845386032. Its totient is φ = 774937152.

The previous prime is 810161579. The next prime is 810161593. The reversal of 810161591 is 195161018.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 810161591 - 2¹⁰ = 810160567 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (810161593) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 17612186 + ... + 17612231.

It is an arithmetic number, because the mean of its divisors is an integer number (211346508).

Almost surely, 2^810161591 is an apocalyptic number.

810161591 is a deficient number, since it is larger than the sum of its proper divisors (35224441).

810161591 is a wasteful number, since it uses less digits than its factorization.

810161591 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 35224440.

The product of its (nonzero) digits is 2160, while the sum is 32.

The square root of 810161591 is about 28463.3376644413. The cubic root of 810161591 is about 932.2317354186.

The spelling of 810161591 in words is "eight hundred ten million, one hundred sixty-one thousand, five hundred ninety-one".